Alpine Valley Rille: Is this
the "Horsehead Nebula" for visual Lunar observers? Maybe. the 700
meter (?)
wide (or narrower) rille that runs across the floor of the Alpine Valley (Vallis
Alpes) is tough visually. However, the Horsehead, B33, is easy for deep sky
imagers while the Rille is almost as tough for imagers as it is for visual
observers (if not tougher). I was happy to get a picture that shows it--if
barely. One of these days I'll get back to it with a larger scope and the
webcamming skills I've begun to accumulate in the three years since I took this
picture.